mchan68 Posted January 15, 2010 Share Posted January 15, 2010 Okay, this may sound like a stupid question I've been wanting to ask for a long time now, but got the chance to post it so here it goes. Out of the thousands upon thousands of 6.0L heads you guys have removed, have you ever noticed the valve bridges don't go on the tops of the valves in any particular orientation, despite the fact that there is an oval end and a round end on each bridge, where it contacts the valve stem? Now, I have always adhered to the practice of re-installing components back to their original locations, in their original orientation just for the sake of it being a good habit. But it seems that even on engines that the bridges have never been removed, I can't seem to find a particular pattern to the way they are supposed to be installed. Neither does the workshop manual specify a way in which they are supposed to go (oval side on the top valve or vice versa). Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted January 15, 2010 Share Posted January 15, 2010 I gave some thought to this once and like you went looking for references about assembly in the manual and came up with nothing. The bridges are a dimensionally symmetrical part with no markings indicating position or orientation therefore "we" can come to the conclusion that it makes no difference with regard to the markings that are there... all you need to know (and you seem to) is to reassemble the engine the way it came apart to preserve wear patterns. Even then, I suspect little would ever come from tossing the bridges into a parts bucket and pulling them out at random and installing them. Not that we would do that. Quote Link to comment Share on other sites More sharing options...
mchan68 Posted January 15, 2010 Author Share Posted January 15, 2010 I gave some thought to this once and like you went looking for references about assembly in the manual and came up with nothing. The bridges are a dimensionally symmetrical part with no markings indicating position or orientation therefore "we" can come to the conclusion that it makes no difference with regard to the markings that are there... all you need to know (and you seem to) is to reassemble the engine the way it came apart to preserve wear patterns. Even then, I suspect little would ever come from tossing the bridges into a parts bucket and pulling them out at random and installing them. Not that we would do that.Now for the interesting question. What if the bridges are being replaced? Not that it has ever been an issue for me personally, YET. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted January 15, 2010 Share Posted January 15, 2010 Non issue with new parts. Quote Link to comment Share on other sites More sharing options...
Mike Jeanotte Posted January 16, 2010 Share Posted January 16, 2010 My though to the round vs oval parts of the bridges is to make up for any possable wear in the valve guides of the 2 valves that the bridges are on??? Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted January 16, 2010 Share Posted January 16, 2010 Even then, I suspect little would ever come from tossing the bridges into a parts bucket and pulling them out at random and installing them. BTDTWF. Been there, done that, works fine. One of my (now retired) co-workers did that all the time... with glow plugs, injectors, push-rods, rocker arms and bridges... every 6.0 he ever took apart... never an issue. I've had to reassemble one of his in the past, and that's how I found all the valvetrain parts-in a box! I try to do my best in returning everything to where it came from, but if something gets mixed up, I don't lose any sleep. Quote Link to comment Share on other sites More sharing options...
DamageINC Posted January 16, 2010 Share Posted January 16, 2010 Yeah, I am extremely finicky about certain parts being installed back where they came from, but after the million 6.0's I've had apart, I've been swapping valve bridges and pushrods like crazy and have never had any problems whatsoever. Not uber-professional sounding but I can't find a reason to call me a bad tech as a result, haha.. Dave Quote Link to comment Share on other sites More sharing options...
Aaron Posted January 16, 2010 Share Posted January 16, 2010 I have an arrangement tray for my racecar, it's designed to hang on top of a carburetor, but I've since modified it. Has spots for all the pushrods & spark plugs and keeps them in order. The push rods and glow plugs go in that. The injectors go in the Rotunda holding fixture. Typically I wash the rocker bridges in brake cleaner, and number them, on the bottom of the rocker bridge with a sharpie, and keep them on the corresponding side of the truck. That way, I know what order they go in, and the number always goes to the bottom. I like putting stuff back where it came from, but there has always been a time where some shit's gotten mixed up and no ill results come of it. Just don't mix up the intake and exhaust pushrods on a big block Chevy or a 3.1/3.4. Guy I worked beside did intake gaskets on a 3.4 and mixed a couple exhaust pushrods up...it wasn't pretty. Quote Link to comment Share on other sites More sharing options...
DamageINC Posted January 18, 2010 Share Posted January 18, 2010 HAha yeah I know a few dudes who've made that mistake before! Dave Quote Link to comment Share on other sites More sharing options...
STROKER_T Posted January 19, 2010 Share Posted January 19, 2010 Ok,while we are on the good inquiry of the valve bridges orientation... how many times have you seen the pushrods have stress cracks right at the center... Got an 07 F550 thats getting head gaskets only and at least 4 pushrods have abnormal lookin cracks....i roll 'em to check for warpness,looks ok,but theres alot of torque on them,can't be good...and when u try to order them they come shorter? I've often wondered if NOT setting the crankshaft dowl to 6'o clock could cause an issue as well,I've seen it done that way Dont mean to hijack the post,but it's related,right? Quote Link to comment Share on other sites More sharing options...
DamageINC Posted January 19, 2010 Share Posted January 19, 2010 You know, I've never set the crank dowel to 6:00... I always make a mental note as I'm starting the job that I "should probably do it" but I always forget to because it's never bitten me in the ass before. Not that I wait until things go wrong for me to decide they're bad.. I just can't see how this is "bad" I guess. I really don't know HOW putting the crank in a different orientaion prior to cylinder head installation is going to make a difference anyway.. the engine's still in time, right? It's not an overhead cam engine where the cam can be out of time and you can smash valves by tossing the head on without making sure there's no room for piston-to-valve clearance. I'm an aboslute nazi about making sure the keyway is at 12:00 whenever I do 4.6 / 5.4 / 6.8 engines because I know the obvious potential for damage. But with the 6.0, it's a pushrod engine, I can't see the damage potential there. Maybe if people gun down the rocker arm plates without making sure the pushrods are seated properly or something, it could bend a pushrod, but I've always tightened everything under the valve covers slowly and evenly by hand and never run into an issue before.. maybe I'm just lucky so far? Dave Quote Link to comment Share on other sites More sharing options...
rlchv70 Posted January 19, 2010 Share Posted January 19, 2010 One hole is oval to prevent the chance of binding. Orientation doesn't matter. Pushrods were shortened to correct a manufacturing tolerance build up issue. Quote Link to comment Share on other sites More sharing options...
STROKER_T Posted January 19, 2010 Share Posted January 19, 2010 So that begs the question,do u replace pushsods as a set? Is the tolerance build up issue the cause for cracks...? Quote Link to comment Share on other sites More sharing options...
Fordracer Posted January 22, 2010 Share Posted January 22, 2010 I don't set the dowel at 6:00 either but I make sure the pistons are down in the bore. You could have clearence problems if the pistons aren't down far enough because the lifters are pumped up and the valve will open farther untill the lifters bleed down. I did head gaskets on one last month and I had it all together on a friday and waited untill monday to start it and it still had no compresion untill it cranked over for along time. I thought the lifters would of bleed down over the weekend but they didn't. Quote Link to comment Share on other sites More sharing options...
joshbuys Posted January 22, 2010 Share Posted January 22, 2010 had same question a while back, asked hotline and they said it didn't matter which way they go - just put back how they came out, i always organize as i'm coming apart so everything goes back the same, but like everyone else here, there have been some mix ups and no issues! Quote Link to comment Share on other sites More sharing options...
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